Refrigerating apparatus



Oct. 25, 1938.

J. KARMAZIN 2,134,665

REFRIGERATING APPARATUS I Filed Sept. 30, 1956 2 Sheets-Sheet l INVENTOR.

j ,fmen z/M ms ATTORNEYS.

Oct. 25,1938. J. KARMAZIN 2,134,665

REFRIGERATING APPARATUS Filed Sept. so, 1936 2 Sheets-Sheet 2 '25 sages and to provide means for causing a recircuposed rows of closed refrigerant conduits or pas- 25 Patented Oct. 25,1938 a 2,134,665

UNITED STATES PATENT OFFICE REFRIGERATING APPARATUS John Karmazin, Huntington, Ind., assignmto General Motors Corporation, Dayton, Ohio, a corporation of Delaware Applicationseptember a, 1936, Serial No. 103.277 7 (01. 62-126) This invention relates to refrigeration and par- Fig. 8 is an enlarged sectional view of the reticularly the cooling elements for refrigerating frigerant inlet connection of the cooling element systems. v e and is taken on the line 88 of Fig. 3;

An object of my invention is to provide an Fig. 9 is a fragmentary side view of a modified. improved cooling element of pressed sheet metal form of cooling element having fins of a different I construction. design; and

Another object of my invention is to unidirec- Fig. 10 is a vertical sectional view of the modtionally assemble a plurality of similar pressed ifled cooling element design showing the fin consheet metal members together and. to bond'the tour. v

10 members to one another to formacooling element Referring to the drawings, for the purpose of 10 having a plurality of refrigerant passages therein illustration, I have shown in Fig. 1 thereof a cqoland integral fin members extending from the. ing element or evaporator generally represented walls of the passages. by the reference character ll. Cooling element A further object of my invention is to provide a or evaporator H, is provided with a liquid recooling element of pressed sheet metal construcfrigerant inlet connection I2 and a gaseous re- 15 tion having refrigerant passages therein and imfrigerant outlet connection I: adapted to be conproved means for stiffening the element and for nected by suitable pipes with any. conventional distributing incoming refrigerant at a plurality refrigerant liquefying and circulating unit (not of points throughout the length of the passages. shown). The cooling element or evaporator I I is 0 In carrying out the foregoing objects it is a constructed of a plurality of unidirectionally sustill further and more specific object of the inperimposed sheet metal fln members It each havvention to provide a cooling element with means ing a plurality of tube elements l5 struck or for distributing incoming refrigerant to a plupressed therefrom and telescoped together to prorality of points throughout its refrigerant pasvide a plurality of parallel and horizontally dislation of refrigerant from one part to other parts sages l6 extending through the structure and disof the element to thereby increase the efliciency posed in vertical rows. In striking each of the thereof. tube elements l5 from the fln members I an Further objects and advantages of the present opening H (see Figs. 4 and 5) is punched from invention will be apparent from the following the sheet metal at the small diametered end of 30 description, referencebeing had to the accomthe tube elements IS. The material adjacent the panying drawings, wherein a preferred form of opening II, at the small diametered end of the the present invention is clearly shown. tube elements It, is cut and deformed as at l8 to In the drawings: provide a perforated wall comprising a vertical Fig. 1 is a side elevational view of a cooling elepart It and two horizontal parts 2| and '22 (see 35 ment constructed in accordance with the present Figs. 4 and 5) extending across the refrigerant invention; passages It formed by the superimposed and-tele- Flg. 2 is an end view. of the cooling element scoped together tube elements IS. The plurality disclosed in Fig. 1; of openings I1 and the wall parts l9, 2| and 22 40 Fig. 3 is an enlarged side view taken in the diprovided in the fin members II are for apurpose 40 rection of the lines 3-3 in Fig. 2 showing the to be presently described.

cooling element partly in section and partly in After stacking a predetermined number of the elevation; fin members H upon one another with the tube 1 Fig. 41s a horizontal fragmentary enlarged secelements l5 thereof in registration or telescoped 45 tion taken on the line 4-4 of Fig. 3 showing the relation to form a cooling element of a certain 45 support of a refrigerant pipe within another resize, a plurality of small plate members 25 (see frigerant p pe; Fig. 3) having a pair of tube elements 26 formed Fig. 5isa vertical fragmentary enlarged section therefrom are placed against the element It at taken on the line 5-5 of Fig. 3 and further showone end thereof. One of the pair of tube elements ing the support of a refrigerant pipe within an .26 of plate members 25 registers and communiother refrigerant pipe; cates with a lower refrigerant passage it of a Fig. 6 is a top plan view of a portion of the horizontal row thereof while the other of the pair small refrigerant pipe; of tube elements 26 registers and communicates Fig. 'l is an end view of the refrigerant pipe with an upper refrigerant passage It. A cap or disclosed in Fig.8; end cover 21 is secured to the edge of each of the end plate members and provide closed U-bends communicating with each pair of vertically arranged refrigerant passages I6. A bracket 23 is then welded or otherwise secured to each of the vertically disposed caps 21 for supporting the cooling element II in a vertical position.

It will be noted that the two fin members I4 adjacent the opposite or right hand end of the structure as viewed in Fig. 3 have the entire vertical end portion of the tube elements l5 cut away to provide clearance for the insertion of stiffening members which in the present invention are in the form of small pipes 3| into the refrigerant passages I6. A late 32 forming one wall of a header33, is p ovided with flanged openings 34 which are secured to the tube elements I5 of the fin members I4 at this opposite end of the structure. A corrugated plate 35, forming the other wall of header 33, is secured in any suitable manner to plate 32. The refrigerant passages |6 formed by thetelescoped tube elements I5 communicate with the interconnected passages of header 33 formed by the corrugations in platev 35. Plate 35 is also provided with a plurality of flanged openings 36 which are disposed in alignment with the openings I! provided in the perforated cross wall part I3 at the ends of.

the tube elements I5. One end of the small pipes 3| is adapted to be secured in the flanged openings 36 of corrugated plate 35. A second corrugated plate 33, having interconnected passages 39, is secured to the corrugated plate 35. The liquid refrigerant inlet connection coupling I2 is secured to a central enlarged portion 4| formed in plate 38. It will be noted that the plate 32 and the first corrugated plate 35 each also have an enlarged portion registering and forming a chamber 42 at the upper portion of the evaporator II. Chamber 42 communicates withthe gaseous refrigerant outlet connection I3 and serves as an equalizing chamber during operation of the refrigerant llquefying and circulating unit connected to the evaporator.

A conduit has itsone end 46 secured to an opening provided in plate 35 to thereby communicate with the header 33 and has its other end 41 secured to an opening in the liquid refrigerant inlet connection coupling I2. By referring to Fig. 8 of'the drawings it will be noted that the end 41 of conduit 45 is cut at an angle as at 43 so as to dispose a portion of the end 43 of conduit 45 in the path of liquid refrigerant flowing into the evaporator II.' The portion 43 of conduit 45 obstructs the flow of liquid refrigerant to the evaporator and this obstruction causes a suction to be created in conduit 45 to thereby draw liquid refrigerant from the lower part of header 33 and causes its flow upwardly in conduit 45. to the chamber 4|. The conduit 45 and its arangement in connection I2 thereby causes a recirculation of liquid refrigerant from one part to other parts of the evaporator II and greatly increases the efiiciency thereof. While I have found that the structure shown will provide sufficient suction pressure in conduit 45 for the purpose disclosed this suction pressure may, if desired, be increased by providing a conventional venturi arrangement as is well known to those skilled in the art.

'By referring to Figs. 6 and 7 of the drawings it will be observed that the pipe 3|, which is inserted in the 0 H of cross wall parts I3, I3, 2| and 22 at'the end of tube elements I5 in fin members I4,'has a rounded end portion 5| and a flattened portion 52 which provides a conduit of elongated contour in cross-section. By locating pipes 3| in the refrigerant passages I6 the evaporator is stiffened and. the structural strength thereof is thereby increased. The ends 5| of pipes 3| are secured to the flanged openings 36 of plate 35 and the pipes 3| extend continuously through the refrigerant passages I6 and termlnatein the end cups 2'! at the one end of the evaporator II. The stiffening members or pipes 3| are firmly supported in spaced relation to the walls of passages I6 by the cross wall parts I3, I9, 2| and 22 at the ends of the tube elements I5. The flattened portion 52 of pipes 3| have a crevice 53 provided in any suitable manner therein and extending from a point adjacent the round end portion 5| thereof throughout the remainder of their length. The opening provided by the crevice 53 andleading into the passage I6 is intermittently interrupted or closed by the plurality of cross wall parts 2| which lie against and are secured to the pipes 3|. These pipes 3| serve to distribute liquid refrigerant, flowing into the evaporator II from header passage 39, at a plurality of points along the length of the passages I6 formed by the tube elements I5 in a manner and for a purpose to be hereinafter described.

In Figs. 9 and 10 I have shown my invention incorporated in an evaporator structure wherein the fin members 6| are complementary parts of other fin members 62. In this form of my invention the two fin members 6| and 62 together with their respective side web portions 63 and 64 are cut or stamped from a piece of metal substantially of a size ordinarily employed to provide a single fln as is fully disclosed in the patent to Jesse G. King No. 2,055,499 dated Sept. 29, 1935. The inactive fin portion of an ordinary fin is thereby utilized to form a second fin which greatly reduces the amount of material necessary to provide the required number of fins on an improved evaporator of the type disclosed.

It is to be noted that the tube elements I5 of fin members I4 may be secured at the same time pipes 3| are securedto plate 35 and to cross wall parts I8, I9, 2| and 22 by brazing or soldering in any manner well known to those skilled in the art in accordance with the steps of assembly employed. All the parts and elements of the improved evaporator disclosed are firmly secured together to provide a unitary structure. The pipes 3| serve to stiflen and increase the structural strength of the evaporator disclosed. The unitary structure has an improved refrigerant fiow circuit embodied therein to thus increase the efliciency thereof as will be apparent from the detailed description of the flow of refrigerant through the evaporator.

Liquid refrigerant flows from an expansion or float valve employed in a closed refrigerating system, with which evaporator II is a part, into the inlet connection I2 of evaporator II. This liquid refrigerant enters the chamber 4| and is directed by the-header passages 33 formed in plate 33 to the open ends 5| of the plurality of pipes 3|. The liquid refrigerant flows through the pipes 3| and is distributed at a plurality of spaced points, through the crevices 52, into the refrigerant passages I5, formed by the tube elements I5 provided on fin members I4. Distribution of liquid refrigerant in this manner occurs simultaneously over substantially the entire evaporator and causes agitation of refrigerant contained therein to thereby create a disturbance of the refrigerant in the evaporator to thus stimulate evapofrigerant from one part of the evaporator to other parts thereof. Liquid refrigerant drawn by condill ration or vaporization. The expansion or float valve and other elements of the refrigerating system are constructed and arranged to maintain a predetermined level of liquid refrigerant in the evaporator II. 'To further stimulate vaporization or bdiling of refrigerant in the cooling element or evaporator II the conduit 45, by virtue of the suction created therein by the *velocity of incoming liquid refrigerant to the evaporator, causes a recirculation of liquid reduit 45 from the lower portion of evaporator ll comingles with the relatively coldincoming liquid refrigerant and thereby quickly increases the temperature of liquid refrigerant flowing through pipes 3i to further stimulate boiling. The distribution of liquid refrigerant at. a plurality of points into the refrigerant passages l6 and the recirculation of liquid refrigerant from the lower part of evaporator H by the conduit it? to a plurality of other parts thereof prevents the formation of quiet or dormant zones within the evaporator. By eliminating the presence of such zones the transfer of heat from the fluid to be cooled by the evaporator to refrigerant contained therein is greatly increased. The fin' members it also aid in transferring this heat to thereby provide an evaporator of maximum eficiency. Refrigerant vaporized in the refrigerant passages it of evaporator ll flows therefrom into the header passages ti and upwardly therein to the gaseous refrigerant chamber M from where it is drawn by suction of the refrigerant liquefying and circulating unit through outlet connection II t.

From the foregoing it will be seen that I have provided an improved unitary evaporator or cooling element for a refrigerating system which can be constructed from a plurality of unidirectionally nested and secured together sheet metal integral fin and tube members. The improved distribution into and recirculation of liquid refrigerant in the evaporator as described and the integral fin and tube elements, together with the integral cross wall parts extending into the refrigerant passages forms a structure which provides maximum and eflicient heat transfer from a fluid to be cooled'to refrigerant in the evaporator while at the same time providing a structure that can be readily manufactured at low cost.

While the form of embodiment of the invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed isas follows:

l. A cooling element for a refrigerating system comprising in combination, a plurality of metal fin members each having a tube portion extending therefrom, said fin members being superimposed one upon the other with the tube portions thereof teles'coped and secured together to provide a closed refrigerant passage extending through the element, a pipe disposed within said refrigerant passage, said pipe. having a crevice in its top surface and extending substantially through-, outthe length of the pipe, means formed integral with the tube portions of said fin members for supporting said pipe in spaced relation to o the walls of said refrigerant passage, and said means cooperating with the crevice in said pipe to provide a plurality of spaced apart openings throughout the length of said pipe for discharging liquid refrigerant into said refrigerant passage at-a plurality of spaced points.

2. A cooling element for a refrigerating system comprising in combination, a plurality of fin members having a plurality of tube portions extending therefrom, sa d fin members being superimposed one upon the otherwith the tube portions thereof telescoped and secured together to provide a unitary structure having a plurality of rows of closed refrigerant passages extending through the structure, a pipe disposed Within one of said plurality of refrigerant passages, said pipe having a crevice in its top surface and extending substantially throughout the length of the pipe, means formed integral with the tube portions of said fin members for supporting said pipe in spaced relation tovthe walls of said one of said plurality of refrigerant passages, and said means cooperating with the crevice in said pipe to provide a plurality of spaced apart openings throughout the length of said pipe for discharging liquid refrigerant into said one refrigerant passage at a plurality of spaced points.

3. A cooling element for a refrigerating system comprising in combination, a plurality of unidirectionally nested members secured together to form a unitary structure, saidmembers including fin portions having tube portions formed integral therewith and telescoped together to provide a plurality of refrigerant passages through the structure, means for connecting an end of one of said passages to an end of another of said passages at one end of the structure, means for connecting the other end of said one of said passages with an end of still another of said passages at the other end of the structure, said last-named means forming a header communicating with all of said plurality of refrigerant passages and being provided with a refrigerant outlet connection, a pipe within one of saidrefrigerant passages and provided with a plurality of outlets for distributing liquid refrigerant ata plurality of points along the length of the said one passage, a liquid refrigerant inlet connection for said cooling element, and a re- 1 frigerant passage communicating with said pipe cluding fin portions having tube portions formed integral therewith and telescoped together to provide a plurality of refrigerant passages through the structure, means for connecting an end of one .of said passages to an end of another of said passages at one end of the structure, means for connecting the other end of said one of said passages with an end of still another of said passages at the other end of the structure, said last named means forming a header communicating with all of said plurality of refrigerant passages and being provided with a refrigerant outlet connection, a pipe within one of said refrigerant passages and provided with a plurality of outlets for distributing liquid refrigerant at a plurality of points along the length of the said one passage, a liquid refrigerant inlet connection for said cooling element, a refrig-' conveying incoming liquid refrigerant to said element directly to said pipe, and a. conduit having one end thereof connected to the lower portion of said cooling element and having its other end communicating with said liquid refrigerant inlet connection, said other elidof said conduit being constructed and arranged to cause liquid refrigerant flowing into the cooling element to create a suction in the conduit for recirculating liquid refrigerant from one part of the'cooling element to other parts thereof.

5. A cooling element for a refrigerating system comprising in combination, a plurality of unidirectionally nested members secured together to form a unitary structure, said members including fin portions having tube portions formed integral therewith and telescoped together to provide a plurality of refrigerant 'passages through the structure, means for connecting an end of one of said passages to an end of another of said passages at one end of the structure, means for connecting the other end of said one of said passages with an emf of still another of said passages at the other end of the structure, said last named meansforming a header communicating with all of said plurality of refrigerant passages and being provided with a refrigerant outlet connection, a pipe within one of said refrigerant passages and provided with a plurality of outlets for distributing liquid refrigerant at a plurality of points along the length of the said one passage, 9. liquid refrigerant inlet connection for said cooling element, a refrigerant passage communicating with said pipe and with said liquid refrigerant inlet connection for conveying incoming liquid refrigerant to said element directly to said pipe, and a conduit having one end thereof connected to the lower portion of said header and having its other and disposed in the path of liquid refrigerant flowing into said inlet connection, said other end of said conduit being constructed and arranged to cause liquid plurality of refrigerant passages through the structure, means for connecting an end of one of said passages to an end of another of said ,passages at one end of the structure, means for connecting the other end of said one of said passages with an end of still another of said passages at the other end of the structure, said last named means forming a header communicating with all of said plurality of refrigerant passages and being provided with a refrigerant outlet connection, a pipe within one of said refrigerant passages, means formed integral with the tube portions of said members for supporting said pipe in spaced relation to the walls of said one of said refrigerant passages, said pipe having a crevice in its top surface and extending substantially throughout the length of the pipe, said means formed integral with the tube portions of said members cooperating with the crevice in said pipe to provide a plurality of spaced apart openings throughout the length of said pipe for discharg-' ing liquid refrigerant into said one of said refrigerant passages at a plurality of spaced points, a liquid refrigerant inlet connection for said cooling element, and a refrigerant passage communicating with said pipe and with said liquid refrigerant inlet connection for conveying incoming liquid refrigerant to said element directly to said pipe.

7.-A cooling element for a refrigerating sys-u tern comprising in combination, a plurality of metal fin members each having a tube portion extending therefrom, said fin members being superimposed one upon the other with the tube portions thereof telescopedand securedtogethen to provide a closed refrigerant passage extending transversely to the fin members, a pipe disposed within said refrigerant passage, said pipe having a crevice therein extending lengthwise thereof, means formed integral with certain of the tube portions of said fin members for supporting said plurality of points along the length thereof.

JOHN KARMAZIN. 

